Suction hood

ABSTRACT

The invention relates to a suction hood, a) which sucks air from a first area to a second area, b) wherein the hood comprises b1) a first sucking means ( 64 ) which pulls the air to the suction hood by generating an at least substantially direct suction to the suction hood and b2) a second sucking means ( 62 ) which pulls the air to the suction hood by generating an at least substantially circular, cyclone or helix movement and a method for generating a air suction by means of a suction hood.

The invention relates to a suction hood, which sucks air from a first area to a second area.

Known or traditional suction hoods, which also can be denominated as destructor hoods, range hoods, kitchen hoods, stove hoods, exhaust hoods, cooker hoods, extraction hoods, cooking canopy or ventilation hoods, are used to remove airborne grease, combustion products, smoke, odours and/or heat and steam, which is generated usually by a cooking process on a cooktop, normally by a combination of filtration and evacuation of the air. They usually comprise three main components: A skirt or capture panel to contain the rising gases (also known as the “effluent plume”), one or more grease filters, and a fan or tangential blower for forced ventilation.

There are two major applications of extractor hoods: vented application, and recirculating application. In a vented application, the output collar of the extractor hood's blower motor is attached to a duct system, which terminates outside of the kitchen. In a recirculating application, a filter containing activated charcoal is used to remove odour and smoke particles from the air, before releasing the cleaned air back into the kitchen environment.

The fans or blowers create, when activated, an area of low pressure which takes effect spherically around the hood.

The airborne grease, combustion products, smoke, odours, heat and steam generated by the cooking of food on the cooktop rise naturally in a vertical motion due to gravity effect, and enter the effective area of the hood to be captured by the low pressure area.

The traditional hoods as described above present at least relatively low efficiency in treating the fumes from the cooktop as they suck-up equally air from the surrounding environment. FIG 1 a shows such a hood 1′, where the gas is sucked in from all sides along paths shown by arrows 74′.

The pressure field 71′ of a traditional hood 1′ over a cooktop 7′ is shown in FIG 1 b. The pressure field represents the effective suction volume of the hood.

In WO 89/11926 A1, a ventilating system has been proposed with nozzles and/or blowers mounted around one or more centrally located exhaust channels.

In is an object of invention, to improve the characteristics of the hood, especially the suction characteristics.

This object is solved by a suction hood according to claim 1. Advantageous embodiments can be derived especially from the dependent claims.

According to claim 1, the invention relates to a suction hood,

a) which sucks air from a first area to a second area,

b) wherein the hood comprises

b1) a first sucking means which pulls the air to the suction hood by generating an at least substantially direct suction to the suction hood and

b2) a second sucking means which pulls the air to the suction hood by generating an at least substantially circular, cyclone or helix movement.

The second sucking means preferably generates a tornado suction in the area underneath of it which allows an improved and focused suction. The combination of a first sucking means and a second sucking means according to the invention enables an improvement of the suction characteristics of the suction hood, as the addition of the second sucking means especially allows an improvement and/or a focusing of the suction in the area underneath the second sucking means which is preferably used for cooking.

In a preferred embodiment, the second sucking means are operated or operatable in a boost mode, so that the second sucking means temporarily boosts the suction of the first sucking means. This allows to boost the suction in cases wherein, for example, a lot of fumes are generated. By activating the boost mode, the fumes normally can be exhausted or reduced more rapidly.

Preferably, the first and the second sucking means are operated or operatable in a pulse working mode and/or alternatively. This enables that, on the one hand, fumes underneath of the second sucking means can be exhausted or reduced more rapidly, when this suction means is active, whereas also fumes from the surrounding area are removed when the first sucking means is active.

In a preferred embodiment, the first and the second sucking means are operated or operatable together, so that the second sucking means continuously boosts the suction of the first sucking means. This enables an improved suction in the area underneath the second sucking means whereas also air is sucked from the surrounding area by the first suction means.

Preferably, an outer suction area surrounds an inner suction area wherein preferably

a) the first sucking means sucks the air to the suction hood mostly through the outer suction area and/or

b) the second sucking means pulls the air to the suction hood at least substantially uniformly through the outer suction area and the inner suction area.

In this case, at least substantially separate suction areas are provided for both suction means so that the suction areas can complement one another without interfering or cancelling each other too much.

In an advantageous embodiment, the air for operating the vortex is sucked in laterally, preferably through lateral openings and/or from the outer suction area. This allows an at least relatively easy feeding of the required air while not affecting the circular, cyclone or helix movement more than necessary.

Preferably, the second sucking means is added or addable by a adding means, preferably dependent on noise, efficiency and/or fumes, the adding means is preferably a switch and/or a sensor driven device. By this, the second sucking means can be added only when necessary.

In a preferred embodiment, the second sucking means is a tornado suction hood and/or the first sucking means is a standard suction hood.

Preferably, the suction hood is a vented and/or a recirculating suction hood. Both embodiments can be used in a preferred way with the suction means.

Furthermore, the invention relates to a method for generating a air suction by means of a suction hood according to one of the preceding claims.

The invention will now be described in further details with references to the schematical drawings in which

FIG. 1 c outlines the concept of a tornado suction hood,

FIG. 1 d shows the pressure field of a hood system according to FIG. 1 c,

FIGS. 2 a to 2 c show an embodiment of the invention and in which

FIG. 1 c outlines the concept of a tornado suction hood 1. The arrows 75 represent the rotating column of air and the arrows 74 represent the suction draft. The combination of these two flows generates the tornado. The air is sucked in through air inlets 101, 102 and therefore pushed into the suction channel 13.

The pressure field 71 of such a hood system 1 is shown in FIG. 1 d. The pressure field represents the effective suction volume of the hood. The generated vortex between the cooktop 7 and the hood 1 sucks in the fume from the cooktop 7 in a swirling motion.

FIGS. 2 a to 2 c show an embodiment of the invention. FIG. 2 a shows a perspective view of the hood with the vortex module 62. FIG. 2 b shows a cross sectional view of the hood, whereas FIG. 2 c shows a bottom view of the hood with the vortex module 62.

The suction hood 6 comprises a first sucking means 64 which to pulls the air to the suction hood by generating an at least substantially direct suction to the suction hood 6 and a second sucking means 62 which pulls the air to the suction hood 6 by generating an at least substantially circular, cyclone or helix movement.

The suction hood 6 comprises a cuboidal upper part 681 under which a lower part 682 with an at least nearly square shaped upper and lower surface, between which four longish side surfaces are arranged. At the sides of the lower part 682, air inlets 601 and 602 are shown.

The upper part 681 and the lower part 682 are arranged directly adjacent, where the common surface is left out to allow the air to flow through.

FIG. 2 b shows a number of suction channels 623 of the vortex module 62 arranged tangentially around the ring shaped area 622. Not shown engines blow the air tangentially from the air inlets 601 and 602 through the outer suction area 634 into the inner suction area 631 of the hood 6 and thus generate the circulating air. The circulating air, in turn, generates a suction which sucks the air into and through the inner suction area 631. The air escapes the suction area at the outlet 633. This is also called tornado aspiration.

A suctions means 64 is arranged centrally in the upper part 681 which is able to suck the air directly upwards through the inner suction area 631 and the outer suction area 634. This is also called standard aspiration.

The hood 6 can be operated with standard aspiration as well as with Tornado aspiration. This can be done in three different ways:

In a first mode, the tornado aspiration is added in a pulse working mode, so that the tornado aspiration and standard aspiration are operated alternatively. For example in the first second, tornado aspiration is used, whereas in the second second, standard aspiration is used. In the next second, tornado aspiration is used again and so on. This means that during the tornado aspiration the suction through the suction area 631 is boosted, while, during the standard aspiration, the suction are is, at least substantially spreaded over the inner suction area 631 and the outer suction area 634.

In a second mode, the tornado aspiration can be operated in a boost mode to amplify the effect of the standard aspiration. This means that, in a normal mode, only the standard aspiration runs, whereas for boosting, the tornado aspiration is added and boosts the suction mostly in the inner suction area 631.

In a third mode, the tornado aspiration is operated together with the standard aspiration so that both modes are operated at the same time. This means that the inner suction area 631 is boosted, while the outer suction area 634 is, at least with respect to the inner suction area 631 operated with standard suction.

LIST OF REFERENCE SIGNS

-   101, 102, 601, 602 air inlets -   13 suction channel -   6 suction hood -   61 first sucking means -   62 second sucking means -   622 ring shaped area -   623 suction channels -   63, 631, 632, 634 suction areas -   681, 682 housing 

1. Suction hood, a) which sucks air from a first area to a second area, b) wherein the hood comprises b1) a first sucking means (64) which pulls the air to the suction hood by generating an at least substantially direct suction to the suction hood and b2) a second sucking means (62) which pulls the air to the suction hood by generating an at least substantially circular, cyclone or helix movement.
 2. Suction hood according to claim 1, wherein the second sucking means (62) is operated or operatable in a boost mode, so that the second sucking means (62) temporarily boosts the suction of the first sucking means (64).
 3. Suction hood according to claim 1, wherein the first (64) and the second (62) sucking means are operated or operatable in a pulse working mode and/or alternatively.
 4. Suction hood according to claim 1, wherein the first (64) and the second (62) sucking means are operated or operatable together, so that the second sucking means (62) continuously boosts the suction of the first sucking means (64).
 5. Suction hood according to claim 1, wherein an outer suction area (634) surrounds an inner suction area (631) wherein preferably a) the first sucking means (64) sucks the air to the suction hood mostly through the outer suction area (634) and/or b) the second sucking means (62) pulls the air to the suction hood at least substantially uniformly through the outer suction area (634) and the inner suction area (631).
 6. Suction hood according to claim 1, wherein the air for operating the second sucking means (62) , which is preferably a vortex module, is sucked in laterally, preferably a) through lateral openings (601, 602) and/or b) from the outer suction area (634).
 7. Suction hood according to claim 1, a) wherein the second sucking means (62) is added or addable by a adding means, preferably dependent on noise, efficiency and/or fumes, b) wherein the adding means is preferably a switch and/or a sensor driven device.
 8. Suction hood according to claim 1, a) wherein the second sucking means (62) is a tornado suction hood and/or b) wherein the first sucking means (64) is a standard suction hood.
 9. Suction hood according to claim 1, wherein the suction hood is a) a vented suction hood, wherein preferably the first area is inside a room and the second area is outside the room, and/or b) a recirculating suction hood, wherein preferably the first area is inside a room and the second area is inside the room.
 10. (canceled) 